This application relates generally to oral implant surgery. More particularly the present invention relates to a surgical guide to be used during dental implant surgery which is used to effect correct placement of a dental implant.
In the healthy non-diseased mouth with natural teeth present, there exists a biologic relationship between the root of a tooth, the crown of a tooth, the bone surrounding the root and the gingiva (soft tissue) surrounding the bone, root and crown of a tooth. In nature, the shape and contour that the gingiva or soft tissue assumes and follows is dictated by the underlying presence and shape of bone. The bone contours around a natural tooth are actually scalloped, with the bone more apical on the facial and lingual aspects of the tooth and more coronal in the inter-proximal area (between the teeth). In a healthy mouth, this scalloping effect is dictated by the cemento-enamel junction (CEJ) of the tooth which itself is also scalloped. It is this scalloping of the bony architecture which lends itself to the formation and maintenance of proper gingival contours including the inter-dental papilla (the small triangular flesh portion adjacent the gum line and located between the teeth).
However, despite best efforts of a person, or because of lack of proper dental care, it may become necessary to replace teeth completely. In these cases, dental implant procedures have proven to be an effective method of restoring both form and function in patients having missing teeth. Implants provide a structure upon which a prosthetic tooth or teeth can be attached and secured in an otherwise edentulous (non-tooth) area. In contrast to using dentures or other tooth born fixed or removable dental bridge systems, implants have the advantage of maintaining bone and not being subject to decay.
Bone support is necessary for proper placement, securement and maintenance of a dental implant. Proper bone support around an implant is also necessary for the development and maintenance of healthy gingival contours, including papilla. Bone growth around an implant follows the shape of the bone-integrating part of the implant. A primary concern in implant dentistry is the precise placement of an implant in its proper location, with appropriate and accurate angulation and rotational position at the time of implant placement surgery. Even the slightest error in implant placement can result in significant complications and or compromises in the stability of the implant, the maintenance of bone, the contours of the gingival tissues, placement of the final prosthesis, stability of the final prosthesis and the overall appearance of the patient's mouth.
Accordingly, it is desirable to provide a prefabricated dental implant surgical guide which ensures the proper placement of a dental implant or implants and its corresponding prosthesis (crown or crowns). One exemplary embodiment of the present invention allows it to be converted from a surgical guide to a dental provisional crown which can then be used to help maintain the hard (bone) and soft (gingival) tissue architecture of the mouth during the healing phase of treatment, with the end result being a final prosthesis that is stable, functional, natural looking and aesthetically pleasing in the patient's mouth.
For such applications, the prefabricated dental implant surgical guide of the present invention may be configured as a surgical guide with a tooth-shaped contour (also referred to as a “tooth contour”) with a post affixed to its apical end, or with a post as an integral part of the entire guide. This embodiment of a dental implant surgical guide is placed into an initial osteotomy site (a surgical procedure in which bone is cut or prepared for the placement of a dental implant) at the time of dental implant placement surgery, but prior to final implant body placement, to ensure and or to correct proper location, angulation, and rotational position of an implant body prior to it's placement.
The present invention in various embodiments is a prefabricated dental implant placement surgical guide which, in one exemplary embodiment, has a post affixed to the apical end of an anatomically correct tooth form. This tooth form can be made to represent any tooth in the mouth in order to have accurate implant placement regarding the tooth to be replaced.
At the time of initial osteotomy site preparation, a small hole is prepared into the jaw bone using conventional dental implant surgical drills. The apical post of the surgical implant guide is inserted into the osteotomy site allowing verification of proper implant placement in location, angulation, and rotational position prior to implant body placement. This is accomplished by viewing the surgical guide in place, then comparing the tooth-contoured part of the surgical guide with some facial and/or intra-oral guideline such as the adjacent teeth, gingiva, shape of the arch and lips etc. This allows for proper implant location and ultimately placement to be verified or corrected prior to implant body placement lending to a more stable, functional and esthetic prosthetic outcome. The apical post of the surgical guide can repeatedly be inserted into the osteotomy site, as the site is further developed and deepened to continuously verify proper position and location of the implant body prior to its placement. This process of trying in the surgical guide with further osteotomy site preparation is repeated until the appropriate final depth of the osteotomy site is achieved. Thus the process of the present invention provides for a verified correct position, location and angulation of the osteotomy site, all prior to final implant body placement. If improper alignment is detected during this verification process, the osteotomy site location, angulation and position can be corrected with minimal damage to the bone.
In another embodiment of the present invention, the prefabricated dental implant surgical guide can be converted into a provisional crown, a plurality of crowns, or a bridge. This is accomplished by removing the finger grip and apical post, or guide post, hollowing out the tooth contour aspect of the guide, and relining the tooth contour aspect of the surgical guide, then reversibly fastening via screw or cement, the tooth contour aspect of the surgical guide to the abutment of an implant body.
In yet another embodiment, the surgical guide comprises a set of anatomically correct tooth forms each having an apical post and finger grip. The apical posts are graduated in length thus constituting a set of surgical guides that are sequentially used as an osteotomy site is created and deepened. In this way the surgical guide set can sequentially provide guidance that the osteotomy site is being correctly prepared.
In yet another exemplary embodiment, the prefabricated dental implant surgical guide comprises an anatomically correct tooth form having a bore through the tooth form into which an adjustable and removable post is placed or threaded. The apical end of the post protrudes through the tooth form and can be lengthened by pushing or screwing the post through the bore. In this way the apical end is lengthened and can be placed into the gradually deepening osteotomy site to insure that the site is correctly prepared. The post can also be removed and an osteotomy drill passed thru the bore to allow for further preparation of the osteotomy site with the guide in place. In another embodiment of the present invention, a bottom face of the apical end of the movable post comprises a marking agent. In this embodiment, the surgical guide is placed in a desired position on the jaw bone at a proposed osteotomy site. Once the correct position of the surgical guide is established, the movable post is pressed downward to engage the bottom face of the apical end with the jaw bone thereby marking the location of the osteotomy site.
In still another exemplary embodiment, the prefabricated dental implant surgical guide comprises a number of anatomically correct tooth forms as a unitary surgical guide. In this case, for example and without limitation, a number of tooth forms can be connected and tried into a series of side by side osteotomy sites as a unit. This allows multiple dental implants to be placed side by side with verification of proper location, angulation, and rotational position.
Thus various embodiments improve the dental implant placement process and allow for proper placement of a dental implant subsequent to osteotomy site preparation. Embodiments act as a prefabricated surgical guide and improve the placement of a dental implant. Embodiments further allow sequential placement of individual prefabricated implant surgical guides to develop sequential osteotomy sites for subsequent multiple side by side implant placement during dental implant placement surgery. Additional embodiments use unitary multi-tooth prefabricated implant surgical guides during dental implant placement surgery where more than one tooth is to be replaced with a dental implant. Other embodiments use a prefabricated dental implant surgical guide having adjustable apical posts for use with deepening osteotomy sites.
These and other embodiments will be come apparent to those skilled in the art upon review of the detailed description that follows.